Illinois police officer shoots former student who opened fire in Dixon High School

A suspect was injured during a gunfire exchange with a police officer after he opened fire at an Illinois school Wednesday morning.

A heroic Illinois police officer prevented what could've been a bloody attack at Dixon High School after he confronted a former student who opened fire in the hallways as seniors rehearsed for their upcoming graduation in the gymnasium nearby.

The 19-year-old suspect, who authorities did not identify, took off running when Officer Mark Dallas approached him shortly after he unloaded several rounds in the school Wednesday morning. Dallas chased him outside, where the gunman continued to shoot at the school resource officer, officials said during a press conference.

"With shots ringing out in the hallways of the school, he charged toward the suspect and confronted him head on," Dixon Police Chief Steve Howell said. "We are forever indebted to his courage and bravery."

Local media identified the alleged shooter as Matt Milby.

Dallas shot and injured the former student during the flurry of gunfire, saving "an enormous amount of lives," Lee County Sheriff John Simonton added.

The teen was taken into custody near the school and is currently receiving medical treatment. His injuries do not appear to be life-threatening. No one else was injured in the attack.

"I know that he's been very sad for a long time," she told WLS-TV."Well, my kid is laying up at the hospital shot. Thank God they didn't kill him, that's a blessing. Thank god he didn't kill anyone else."

Milby said she grew up with Dallas and thanked him for stopping her son.

"I think in most cases they would kill him," she added.

All public schools in Dixon, located about 100 miles outside Chicago, were put on lockdown amid the incident. Only Dixon High School remained closed off later Wednesday afternoon as officials continued to investigate the shooting.

School Resource Officer Mark Dallas (pictured) shot and injured 19-year-old former student Matt Milby, who fired shots at Dixon High School on Wednesday in Dixon, Ill. (Facebook)

Student Brandon Stehl was sitting in the gym waiting to learn about where he would receive his cap and gown when he heard gunshots nearby. Wednesday was slated to be the senior class' final day at Dixon High School, whose famous alumni include President Ronald Reagan.

"All of a sudden out of nowhere, you just hear pop, pop, pop!" he told NBC Chicago. "Sounds like firecrackers, and then there's dead silence. Then all of sudden a teacher comes in and says, 'Go, go, go!' and everybody floods out of the school and into the cafeteria."

Dallas, who is being lauded as a hero by the community, was placed on paid administrative leave following the incident, per department policy.

"Today, we should all be very thankful to school resource officer Mark Dallas for his bravery and quick action to immediately diffuse a dangerous situation at Dixon High School," Gov. Bruce Rauner tweeted.

Rep. Adam Kinzinger, who was briefed on the situation by Simonton, praised the quick response by authorities.

Officials say a police officer has shot and wounded a gunman at a northern Illinois high school. (Rachel Rogers/AP)

"As we continue to gather more information about the shooting incident at Dixon High School this morning, I extend my deepest gratitude to the Dixon Police Department, and especially the School Resource Officer on-site for their swift action today in keeping our students, teachers and community safe," he said in a statement.

Ahead of the incident Wednesday, there had been 21 school shootings in which someone was either hurt or killed so far in 2018. That averages out to about one incident a week, with the most recent being in Palmdale, Calif., on May 11.

One person was shot in the arm, and the suspect was taken into custody.

Simonton noted the Dixon school district has been working with law enforcement to develop a plan of action in wake of recent high-profile school shootings like the one in Parkland, Fla., which left 17 dead.

"I could happen here. It doesn't matter how large or small your community is. It happened here today," Simonton said. "The bottom line is, they were prepared."

The first school resource officer was assigned to Dixon High School in 2000 and a second was assigned to Regan Middle School a year later to "help prevent school violence," according to the school's website.